Three short lines, and the poem manages to hand over a whole prescription. Its title promises medicine, yet nothing in it comes from a pharmacy. The remedy is wind, oysters and a long walk. The central idea is that being well might have more to do with appetite, movement and open air than with the careful management of a body. The poem is not interested in the invalid's routine. It is interested in escaping it.
The last line holds the key. "Clock and caudle" pairs two things that belong to the sickroom. A caudle is an old-fashioned warm, spiced drink, traditionally given to the ailing, and the clock stands for the schedule of doses and rest. One is soft and the other mechanical, but together they suggest being looked after, timed and kept indoors. Against them the speaker sets a walk. The verb is "keep," and what it protects is "myself." The poem never says the speaker is ill. Judging by that phrasing, the danger is more of being slowly turned into a patient, or into someone whose days are run by a timetable. Whether that is literal illness or a figure for dull routine, the poem leaves open.
The construction is quietly clever. Counting syllables, the lines run five, eight and ten, so each is longer than the last. The poem starts out as a breath and ends on a full stride, which suits a piece about walking. There is no end rhyme, and none is needed. The sound does the work instead. "Wind among the sands" is made of soft, hushed consonants, w, n, d and s, and it sounds a little like the thing it names. The final line is harder: "walk," "keep," "clock" and "caudle" repeat that clipped k sound, so the line seems to tick even as it rejects ticking. One might also hear a pun in the first word. "Wind" is weather, but it is also what one does to a clock. The poem opens with a word that quietly contains the thing the speaker is walking away from.
The grammar moves in a telling way. The first line is a fragment with no verb and no "I," as though the landscape exists before the speaker arrives. Only in the second line does "I eat" appear, plainly and with some relish. In the third the subject drops away altogether. "Walk" simply continues the sentence, the speaker's action running on without the pronoun, and "myself" appears only as something to be defended. The self goes from observer to eater to someone guarding its own freedom, all in three lines.
Time is handled just as carefully. "All afternoon" is a measure of time, but a generous and unscheduled one, the opposite of a dose taken on the hour. Eating oysters for an entire afternoon is a small act of excess, a pleasure rather than a duty. Together with the sands, the oysters hint at a seaside setting, though that is an inference from the imagery, since the poem never names a place. The setting matters less than the contrast it sets up. The remedy tastes of brine and wind, while the thing refused is warm, sweet and sickly.
What makes the poem worth reading is how much it does by turning one word around. "Medicine" usually suggests something measured out and endured, and the poem quietly redefines it as something enjoyed. It does this without argument or explanation, trusting an odd, archaic word like "caudle" to carry the contrast. The poem's brevity also fits its idea. A longer poem about escaping routine might feel like routine itself, but this one spends only a few seconds of the reader's time and then lets them go.